Improvement in hydraulic elevators



M. L. WYMAN. Hydraulic-Elevator. No. 203,520. Patented May 7, 187s.

UNITED STATES PATENT OEEIoE.

MARTIN L. WYMAN, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN HYDRAULIC ELEVATORS.

Specication forming part of Letters Patent No. 203,520, dated May 7, 1878; applicationlfiled January 11, 1878.

To all whom it may concern: v

Be it known that L, MARTIN L. WYMAN, of Boston, county of Suiiolk, State of Massa-chiisetts, have invented an Improvement in Hydraulic Elevators, of which the following is a specification This invention relates to hydraulic elevators; and consists in a hydraulic elevator having two or more lifting capacities depending upon the effective area of piston-surface acted upon by the water coming in from the main or supply valve or valves, and mechanism to operate them by a single hand-rope, to control the flow of water to make available the smaller and then the larger capacity, and to operate them simultaneously to completely shut off the flow of water for both capacities, to keep the car at rest; also, in a hydraulic elevator of two or more lifting capacities, substantially as hereinafter described, the combination, with the hand-rope, of a stop to retard its movement just before opening the valve for the second or larger capacity; also, in the combination, in a hydraulic elevator of two or more lifting capacities, as hereinafter described, of a hand-rope and a stop with an automatically-operated releasing device to release said stop, to permit the movement of the rope, to open the valve for the second or larger capacity; also, in the combination, with the releasinglever, of a piston operated by the pressure ofthe iiuid, so as to actuate the releasing device, substantially as described. Figure 1 represents, in side elevation, a sufficient portion of an elevator to illustrate an embodiment of my invention; Fig. 2, a front elevation; Fig; 3, a section through the valve mechanism and cylinder; Fig. 4, a detail of the stop mechanism, which, through the hand-rope, regulates the openings of the valves. Figs. 5 and 6 represent modifications of stop mechanism for the hand-rope, and Fig. 7 represents one of the valves.

The main cylinder c, plunger b, and piston head c and its valve d are substantially as in my patent No. 174,171, February 29, 187 6, t0 Whichl reference may be had.

In this instance of my invention I have loy cated the plunger within the cylinder, so that the plunger is moved downward to lift the car.

The plunger carries a proper number of sheaves e, which bear upon the ropes or other usual connections f, which extend to the elevator-car g, in order that such plunger,by its own gravity, may partially or fully counterbalance the weight of the car. rllhis connection also prevents slack in the ropes in case the 'c ar meets with obstruction while descending, and obviates the escape of the ropes from the sheaves.

The fluid in the cylinder is the motor for the ascending car, and the car, when descending by its own or additional weight, lifts l vided with collars 2 3 4, the ones 2 and 3 be ing fixed thereon, while the one 4 is so c0nnected with such rod as to be moved longitudinally thereon for a short distance.

The collar 2 operates the inlet-valve 5, which permits the fluid to ow from the main or other supply pipe, connected at m with the chamber n, into the passage 8, through passage o, into the cylinder above the piston head c, such fluid, so admitted by this single valve 5, setting in motion the plunger, an'd consequently the car, for its rst or smallest capacity. At this time the iiuid in the annular space p, between the plunger and the in# terior of the cylinder a, passes through the valve l in the piston-head. If it becomes necessary to lift a heavier load than can be lifted by the first or smallest capacity, this valve-rod is moved a little farther, so that the collar 4 will be moved to open the valve 9 for the larger capacity. During this last movement of the valve-rod the collar 2 yet farther opens the inlet-valve 4. This ope-ration of these two valves permits the full pressure of the water in the main to become eii'ective upon the entire face of the piston-head, all pressure of uid at the under side ofthe head being reA moved, for the water at the under side of the piston-head in the annular space between the plunger and. cylinder is permitted to escape through the passage covered by valve 9 into the drain through outlet 15 as the piston descends.

The collar 4, which operates this valve 9 to call into play the second capacity of the ele-l vator, is connected with the valve-rod by means of a pin, 10, which extends through an opening in the rod, (see Fig-3,) or vice versa, suitable friction devices (shown in this instance as springs 12) holding the collar 4 until the ends of the. stop,- during the movement of the rod, strike the pin 10. This provision for lost movement between the-valve-rod and collar 4 for the valve of the second capacity permits me to operate the valves for the rst and second capacities consecutively, and: to fullyY close lthem simultaneously. Y It is found very desirable, and essentially necessary, in hydraulic elevators of two or morev capacities .that the valves controlling the flow of water for the second capacity be simultaneously closed, for `shouldthe larger capacity be closed first, andthe car berelieved of weight, leaving the weight thereonwithin the power of the smaller capacity to lift, then such smaller capacit-y: will at once elevate the oar, which is-dangerous, yand. is asourceof great annoyance.'

By means of but a single hand-ropeona hydraulic elevator ofrtwo or moreA capacities, if the valvefor. each lcapacity :Were cutl olf consecutivelyinthe order reverseto thaty at which l,they werei let on, the car, before it reached thevupper story, would strike ythe stop on ithe hand-rope vvand close ythe larger capacity, thereby stopping thc car below the level of the iioor; and it is therefore obvious (it being understood the car wouldhave to move about three feet between the timesof operating such valves) that, `at ,the upper story, it would be impossible, with the larger4 capacity in operation, to` stop ,the car at the: level of such rippen-1110.01", but by closing each capacity simultaneously the car can be instantly stopped, and be retained in any position.

When the valve-rod is being moved to close the valves 5 and 9 of the smaller and larger capacities,y the collar 2 partiallyclosesithe valvef;y but during this movement ofthe valve-rod to .sopartiallyclose 'it the collar 4 is held by thefriction'devices, and the valve 9 is not .moved 5 but the continuation lof .the movement of the valve -rod finally picks up the collar 4, andthereafter the collars 2 and 4 move in unison, and each permits itsvalveto more capacities, the operator,by carelessness,

scribed. come to its seat at the same instant. .The

is liable to pull the hand-rope far enough to open the larger capacity whenY the smaller capacity would have been amply sufficient. To indicate to the operator the point at which the larger capacity is ready to be opened for operation, I have arranged a stop, it being `shown in Fig. 4. by the letter t. This stop is pivoted at u, and is provided with a weight, w, to keep it in such position that the lever t' will strike and be positively stopped when the operator moves the hand rope far enough to open the valve of the smaller capacity.

li' the smaller capacity is insufficient to lift Athe load, the pressure of the fluid in the cylinder becomes equal to the pressure in the main, and the fluid, passing from the cylinder through the pipe a2 into a chamber, a, operates in any usual way a` piston, a3, which acts to liftya releasing-lever, a5, weighted at ai, so as to riseat anydesired pressure and release the stopt, permitting l it toturnfrom under the lever, after which the operator can move the hand-rope to open the valve for. the larger capacity.V Thisit will bey noticed, isa positive stop and the operator cannot usethe largercapacity unless the pressure of the fluid inthe cylinder is sufficient to releasethe stop.

i In the drawing, Figs-5 and 6, Ihaveshown modified forms of stops, which are not pos1- tive, but-which v are sufficient toindicate to the operator the opening-points of ,the valves of the largerV capacity.

InA Fig. 5.the shaftbz, carrying.Y the sleeve c2, has a pinion, d2, which engageswith a rod, e2, on the. link k, which operates avalve-rod, such` as l. Nearthe pinion ,d2 .isa cam,;f2, having a stop, vg2,- which, as the shaft b2 is rotated, meet-s the studh2 onthe lever 2, weighted at jz, the stop meeting the stud or` a roller thereon just before the ylarger Acapacity commences to` open.

In Fig. 6, I have xed Aupon ,thehandrope It a stop, k2,.which,just as the largercapacity valve is to be opened, meets a weight, Z2, .and before the larger capacity can be opened this weight must be lifted. When lifted sufficiently far it is caught by a catch, m2.

yThe form shown in Fig. 5vis quite sufficient for intelligent operators using passenger-elevators; but the other forms are preferred for use in warehouses, where less care is exercised.

AThe vcover for ,the valve-box .ris omitted y,in

the drawings. Y

, It is obviousthat instead of the valves herein shown any otherwellfknown valves may be used, they'beingv operatedl in the order dey, 1. The combinatiominahydraulic` elevator having two or moreliftin g ,capacities depending upon the effective area of Vpiston-surface vacted upon bythe watervcoming against it from the main, of valves and mechanism to operate themv by a single` hand-rope, to. control the flow of water to make available. the

. smaller and then .the larger liftingcapacity of I the elevator, andto operate them simultaneously to completely shut off the ow of water rope may be moved to open the valve for the larger capacity, substantially as described.

4. A stop and releasing mechanism, in com.- bination with a piston set'in motion by the pressure of the Huid in the cylinder, the piston actuating the releasing mechanism to release the stop, substantially as described.

In testimony whereof I have signed my name to this speciiication in the presence of two subscribing witnesses.`

MARTIN L. WYMAN.

Witnesses G. W. GREGORY, W. J. PRATT. 

